Get audio into your Mac

You can use your Mac to record late-night jam sessions, snatch work-in-progress tunes hummed into a microphone, turn the MIDI data transmitted by a keyboard or drum pad into something worth listening to, and capture LPs and convert them into samples. But to do any of these things, you’ll need to carefully consider the type of input device that will best suit your needs and help you get high-quality sounds into your Mac.

Microphones. For musical matters, a Mac’s built-in microphone is a terrible choice. It offers too little fidelity and picks up far too much room noise. Headset mics aren’t much better, since they’re not very versatile (try using one to record a guitar), and the headset microphones that people often use for Skype and iChat calls or podcasting don’t provide broad enough fidelity. When you need to record a voice or instrument, a real microphone is the only way to go. You have a couple of options in this regard. The most convenient is a microphone that plugs directly into your Mac’s USB port. In most cases, these microphones don’t require any additional software to work.

Using a USB microphone was once a compromise—there weren’t a lot of them around, and those that were available didn’t offer the kind of quality professionals demand. That has changed.

It’s convenient to be able to control the input gain, as you can do on a microphone such as the Samson G-Track.

Audio quality is, of course, your key concern, but there are other features to consider as well. For example, you’ll avoid some cable clutter if you choose a microphone with a headphone port that lets you monitor not only the sound coming into the mic, but also your Mac’s audio (useful when you’re overdubbing a part, for example). Marshall Electronics’ USB.009 and Samson’s G-Track both offer headphone ports and provide a way to monitor sound from the mic as well as from the Mac it’s plugged into.

Having a control knob to adjust a USB microphone’s input volume, or gain, is helpful in that it’s less hassle than having to dig down into the Mac’s system preferences or an application’s settings. Rode’s Podcaster and the previously mentioned USB.009 and G-Track allow you to control input gain.

But there are times when USB microphones and OS X 10.5 don’t cooperate. When using a USB microphone, you may occasionally encounter bursts of static. To avoid this issue, try the following solution.

Launch Audio MIDI Setup (/Applications/Utilities). From the Audio menu, choose Open Aggregate Device Editor. In the sheet that appears, click on the plus-sign (+) button to add an aggregate device. In the Structure area below, enable the Use option next to the driver used by the USB microphone (USB Audio CODEC, for example). Enable the Clock option next to that device and click on Done. When you want to use that microphone, choose Aggregate Device as the input source—either within an application or from the Sound preference pane’s Input tab.

Audio Interfaces. Alternatively, you can use a microphone with an XLR connector that plugs into a USB or FireWire interface. These audio interfaces, made by companies including M-Audio, Mark of the Unicorn (MOTU), Digidesign, and Edirol, feature at least one audio input and, in some cases, MIDI in and out ports as well.

Many multiple-input audio interfaces require that you control the interface via software.

Audio interfaces generally require a separate software driver. Some include an application or preference pane for controlling the functions of the interface. For example, M-Audio’s Fast Track Ultra eight-port USB 2.0 interface requires you to open its preference pane within OS X’s System Preferences to control the device’s gain, pan, and output. I can control my older MOTU 828mkII audio interface either directly on the device or on the Mac through the company’s CueMix DSP application.

The advantage of these multiport interfaces is that you can use them to record multiple channels at once—a band full of instruments or even four people participating in a podcast’s roundtable discussion (see our podcasting guide for more info). And recording multiple inputs at the same time doesn’t require a high-end audio application—Apple’s GarageBand will do the trick.

Choose a different input source for each GarageBand Real Instrument track.

To do so, launch GarageBand and open its Preferences menu. Click on the Audio/MIDI tab and choose the audio interface in the Audio Input pop-up menu (and in the audio Output pop-up menu as well if you want to monitor audio from the interface). There’s no need to configure MIDI input separately. GarageBand will automatically detect any devices connected to your Mac that bear MIDI inputs.

Close GarageBand’s preferences and choose Track: New Basic Track to create a new hardware instrument track. Continue adding tracks until you get as many empty ones as you need. Select a track and choose Track: Show Track Info. In the Info panel that appears, choose your first input from the Input Source pop-up menu—Stereo 1/2 (MOTU 828mk2), for example. Continue selecting other tracks and choosing appropriate inputs for them. When you’re ready to record, just click on the red icon next to each track to enable recording, and then click on the master Record button at the bottom of the window. GarageBand will record each record-enabled track separately.

Microphone Interfaces. Not everyone needs a large audio interface. Some people may object to their bulk and the expense of buying one, or may find that they need just a single microphone input. A more portable option is a USB adapter that plugs directly into a microphone via an XLR connector. Soundtech offers the LightSnake Microphone to USB Cable, a 10-foot cable featuring a female XLR connector on one end and a USB connector on the other. With this cable you can plug an XLR microphone directly into your Mac and record—no additional software required.

Regrettably, the LightSnake cable doesn’t provide phantom power—the current some microphones require to operate. If you need phantom power, however, there are other options. CEntrance’s MicPort Pro is a 24-bit, 96kHz USB mic preamp that provides 48V phantom power. Blue Microphones’ Icicle costs about half as much, but offers 16-bit, 44.1kHz audio only.

Off the Record. Those interested in pulling samples from LPs or archiving their precious record collections need to find ways to move audio from turntable to Mac, and turntables present a unique problem. Unlike other audio sources, they use a special kind of filtering—called an RIAA Equalization Curve—that requires the turntable to play through a device (a receiver or preamplifier, for example) designed to deal with that filtering. There are a few options for recording music from turntables.

The least expensive is to locate an auxiliary output on a stereo receiver plugged into the turntable, and run a stereo RCA-to-mini-plug adapter cable between the receiver and the Mac’s audio input port. Choose that input in the Sound preference pane and capture the turntable’s output with any audio editor (including GarageBand).

Another option is Griffin Technology’s iMic USB Audio Interface. Although you can use the iMic with just about any audio source (a tape deck or microphone, for example), it has a special talent for recording directly from turntables, as the Mac software included with it—Final Vinyl—is smart about the RIAA Equalization Curve.

Finally, you can eschew go-between boxes altogether by purchasing a USB turntable. These turntables are offered by Audio Technica, Ion Audio, Sony, and Numark at prices ranging from less than $200 to $400-plus.

[Senior Editor Christopher Breen is a musician and the host of the Macworld Podcast.]